Water jets have been used to cut food products for years. The advantages are numerous: there are no blades that need to be sharpened or replaced, no dust is created, and cuts can be quick and clean. The cutting is done with a thin, high pressure, high velocity stream of water or other fluid. Pressurized water is ejected from a very small orifice to create the jet. When the product touches this jet, a thin slice is removed without any appreciable water being absorbed into the product.
Shapes can be cut with one pass of the product beneath the water jets. Circular or pie shapes are often desired. These shapes require more than one fluid jet if the product to be cut is on a conveyor belt running in one direction as may be desirable. Since at least two jets must be used, they must be precisely coordinated to accurately produce the desired shape.
Various ways have been taught to move the water jets relative to the product to be cut. U.S. Pat. No. 4,266,112 (Niedermeyer) teaches the use of a conveyor belt on which the product is moved while jets mounted on solid frames move transversely to the direction of travel of the conveyor belt to cut different shapes. All cutters on the frame move in the same direction. Movement of the frames is accomplished with a complicated sliding arrangement, such as that illustrated in FIG. 10.
Niedermeyer also discloses an embodiment that uses a continuous chain with a cutter attached to one side. See FIG. 12. The cutter is actually linked into the chain such that the length must be adjusted by placing an idler on one side of the chain if additional cutters are added. No mention is made of any cutters being placed on more than one side of the chain. The disclosure states that this embodiment is to be used to make transverse cuts (see col. 9, line 63 through col. 10, line 49).
U.S. Pat. No. 4,735,566 (Squicciarini) discloses the general concept of using a fluid jet to transversely cut a ribbon of extruded dough that moves past the fluid jet on a conveyor. However, no other shapes are suggested.
U.S. Pat. No. 5,083,487 (Croteau) discloses a plurality of water jet cutters displaceable laterally and independently to cut shapes in a moving web (see FIGS. 5a-f). The cutters are each driven by their own belt, therefore, precise synchronization between the independent belt drives is required if particular shapes are desired that require two jets to work together.
The devices currently in use, as exemplified by those described above, do not effectively and efficiently solve the problem of cutting special shapes such as circles and pie segments without excess complexity and precise positioning of the water jets. Accordingly, the present invention was developed, and provides significant advantages over previous devices or methods to cut shapes with fluid jets.